Protecting the Earth from an extinction-threatening asteroid has in the past been left up to Hollywood, which has deployed a barrage of special effects box office blockbusters that have kept deadly space rocks from smashing our planet into oblivion.

NASA's Dawn spacecraft has sent back the first images of the giant asteroid Vesta from its low-altitude mapping orbit. The images, obtained by the framing camera, show the stippled and lumpy surface in detail never seen before.

Asteroid -- An asteroid, also called a minor planet or planetoid, is a member of a group of small, planet-like bodies that are part of our solar system. They are believed to be remnants of the interstellar clouds, nebula, that were not incorporated into planets during the formation of the solar system.
The largest asteroid in the inner solar system is Ceres with a diameter of 1003 km. It also was the first to be discovered, by Giuseppe Piazzi on January 1, 1801. Nowadays, over 9000...

Asteroid Belt -- The Asteroid belt is a region of the solar system falling roughly between the planets Mars and Jupiter where the greatest concentration of asteroid orbits can be found.
It is believed that, during the first million years of the solar system history, planets formed by accretion of planetesimals. Ripetute collisions led to the familiar rocky planets and to the gas giant's cores.
However, in this zone of the system the strong gravity of Jupiter inhibited the final stages...

Near-Earth Asteroid -- Near-Earth asteroids (NEAs) are asteroids whose orbit intersects Earth's orbit and which may therefore pose a collision danger, as well as being most easily accessible for spacecraft from Earth.
In fact, some near-Earth asteroids can be reached with much less Î”V than the Moon. The most famous near-Earth asteroid is 433 Eros that was visited by NASA's Near Earth Asteroid Rendezvous probe.
A few hundred such near-Earth asteroids are known, ranging in size up...